Our earth is made up of nearly 71% water, which is absolutely wonderful, considering that the human body itself is approximately 65% water and that while man can live for two to three weeks and possibly even longer without food, he cannot live more than perhaps three to five days without drinkable water. However, despite the fact that the earth is majority water, approximately 97% of all water on our planet is salt water and therefore undrinkable. Further, the majority of our fresh water is retained in ice caps and glaciers, leaving humanity a paltry 1% of water that is readily available and drinkable, to serve all of humanity on earth.
The question that must be asked is why is the majority of our water, salty? It isn't from our rain, which is for the most part, drinkable as is, and of immense importance for crops, animals, and agriculture. Instead, our oceans are salty, because of the mineral salts that dissolve into the ocean from rocks and other mineral formations, as well as from gaseous substances that burst or leak through the earth's crust. In our water cycle, the sun essentially heats water in our oceans, which basically then vaporizes or evaporates pure water from our seas, taking then these vapors up into the atmosphere, where eventually clouds are formed, and subsequently rain is released back onto our earth.
The bottom line is that our oceans and seas are destined to remain salty, and by definition to remain undrinkable because the consumption of salt water, increases dehydration in your body, as your kidneys cannot excrete efficiently the excess salt brought into our bodies, and must have good fresh water instead in order for our bodies to function properly. This then points to the extreme importance of drinkable water for humanity and for civilization in general.
It should come as no surprise, then, that mankind has for centuries worked diligently in trying to come up with solutions that will efficiently and effectively desalinized water. The two main ways to accomplish desalinization is from either the distillation of the seawater or through reverse osmosis. Distillation is the art of first boiling water to remove the impurities from the water and then condensing the steam back into what will now become purified or distilled water. In regards to reverse osmosis, water is first forced through a semi-permeable membrane which effectively removes most of the impurities of the water, and subsequently creates drinkable water.
While a lot of progress has been made over the years in effectively desalinizing water, these processes require both time and energy to accomplish their objectives, to which the payback crossover point is not necessarily easily to determine. That said, because of the great vitality of water to sustain life on our planet, efforts must be continued to be made to efficiently and to consistently provide good clean water to populations throughout our world. Water is far too great of resource, to simply take for granted, because good clean water is a fundamental need to sustain life on this good earth, for one and for all.